Despite CEO Steve Ballmer's claims last year that Linux vendors are violating some 235 Microsoft patents, the company seems to be trying harder to learn to live with the open source world  and vice versa.

Redmond said Monday it will co-sponsor the Open Source Census (OSC), a project aimed at getting a handle on who uses which open source software (OSS). Statements on the group's site, describe the OSC as "a global, collaborative project to collect and share quantitative data on the use of open source software in the enterprise."

OSC invited Microsoft (NASDAQ: MSFT) to participate because a lot of OSS runs on Windows. In fact, invitations to participate went out to more than just Microsoft.

"We reached out to the whole gamut of players [in the OSS community]," Kim Weins, OSC spokesperson and vice president of marketing and products at open source developer OpenLogic, told InternetNews.com. "They [Microsoft] need to participate in the open source ecosystem because so much open source software runs on Windows," she added.

Microsoft officials confirmed that they've signed on as a sponsor.

"Our customers, partners and developers are working in increasingly heterogeneous environments, and our participation in industry projects like the [OSC] are relevant for the ecosystem in which we participate," Sam Ramji, senior director of platform strategy at Microsoft, said in a statement that echoed Weins.

Ramji reeled off a list of other OSS projects Microsoft has participated in over the past year or two  "Apache, Firefox, and Eclipse; community development projects on Sourceforge and Codeplex; and partnerships with commercial open source vendors like JBoss, Zend (PHP), SugarCRM, and SpikeSource." It also launched its own site for OSS, dubbed Port 25.

Additionally, in March, Microsoft promised to collaborate with the Eclipse foundation's Standard Widget Toolkit development team to allow Eclipse to use the Windows Presentation Foundation, the graphics platform underlying Windows Vista and Windows Server 2008.

That comes on the heels of Microsoft's announcement in February that it will post thousands of pages of interoperability documentation on the Web in order for competitors  including OSS developers  to create products that work with Windows.

What's the real agenda?

Still, it's hard, even for long-term Microsoft watchers to discern where the company's real motives lie.

"I don't know what to make of it, whether it's a p.r. stunt or more of a change in direction," Dana Gardner, principal analyst at Interarbor Solutions, told InternetNews.com.

Gardner did note Microsoft's recent moves to try and make nice with the open source community. However, it may be easier to gather a census of what OSS products are in use than to get a clear read on Microsoft's intentions.

After all, you can't feel totally comfortable participating with a group of developers and companies whose goal is to make commercial software developers  especially Microsoft -- obsolete.

"The primary goal of the [OSC] is to promote the use of more open source software in the enterprise . [and it] will also help the open source community and open source vendors to quantify how much their software is deployed," the OSC statement said.

That certainly sounds like a potential threat to Microsoft's hegemony.